The hymns are philosophical to the extent that they attempt to explain the mysteries of the world not by means of any superhuman insight or extraordinary revelation, but by the light of unaided reason. A striking aspect of the Vedic hymns is their polytheistic character. A great many gods are named and worshipped. It believes that God is deva because He gives the whole world. The learned man who imparts knowledge to fellow man is also a deva. The sun, the moon and the sky are devas because they give light to all creation. Father and mother and spiritual guides are also devas.
Monotheism is an important tendency that has been derived from the Atharva Veda. It believes that the Supreme can only be one. There cannot be two supreme and unlimited beings. Some of the hymns of Rig Veda had brought in the concept of the Supreme as He or It. The apparent vacillation between monotheism and monism, a striking feature of Eastern as well of Western philosophy, revealed itself here for the first time in the history of thought through the Vedas.
There is no basis for any conception of unreality of the world in the hymns of the Rig-Veda. The world is not a purposeless phantasm, but is just the evolution of God. Wherever the word Maya occurs, it is used only to signify the might or the power. Yet sometimes Maya and its derivatives like mayin are employed to signify the will of the demons, and we also find the word used in the sense of illusion or show. The main tendency of the Rig-Veda is a naive realism. Later Indian thinkers distinguished five elements, ether or akasa, air, fire, water and earth. But the Rig-Veda postulates only one, water. It is the primeval matter from which others slowly develop.
The Vedic Religion does not seem to be an idolatrous one. There were then no temples for gods. Men had direct communion with gods without any mediation. Gods were looked upon as friends of their worshippers. "Father Heaven", "Mother Earth", "Brother Agni" these were no idle phrases. There was a very intimate personal relationship between men and gods. Religion seemed to have dominated whole of their life. The dependence on God was complete. People prayed for even the ordinary necessities of life. "Give us this day our daily bread" was true to the spirit of the Vedic Aryan. It is the sign of a truly devout nature to depend on God for even the creature comforts of existence. As it has been already said, it has the essentials of the highest theism in the worship of Lord Varuna. It has been said that if bhakti means faith in a personal God, love for Him, and dedication of everything to His service and the attainment of Moksha or freedom by personal devotion, surely will be present in Varuna worship.
Sin according to the Vedic philosophy is alienation from God. The will of God is the standard of morality. Human guilt is short-coming. Individuals sin when they transgress the commands of God. The gods are the upholders of the Rita, the moral order of the world. They protect the good and punish the wicked. Sin is not merely the omission of the external duties. There are moral sins as well as ritual sins.
The ascetic tendency of the Indian Philosophy has also been incorporated by the Vedic teachings. It can be concluded saying that the Indian Philosophy during the Vedic period was closely associated with some important tenets like nature worship, monotheism and even polytheism sometimes.